well imo it doesn't sound ? like its getting fuel to the cylinder via the carburettor, this could be down to various reasons from a simple clogged fuel filter and dodgy fuel lines, to a clogged gauze screen in the carb, a stuck metering needle in the carb, and a carb kit not properly fitted? a porous impulse line could also be the problem, or an air leak? the carburettor relies on vacuum created by the piston going up and down the cylinder, so if the crankcase has a leak (usually seals) then obviously vacuum will not be created resulting in no fuel getting to the carb. it could possibly leak at the intake boot or if the carb isn't seated properly. I'm not familiar with this models pulse line bout if it has the type which passes through the intake boot then make sure its mating up properly to the pulse/vacuum orifice in the carb, the rubber intake boot should have a steel spacer/washer insert to enable the intake boot to keep shape under vacuum and to maintain a good seal to the carb.
you say you rebuilt it ? this is a broad brush , do you mean you stripped the engine and re-built that ? if so, did you us an oil compatible gasket sealer between the cylinder and sump/pan when putting it backtoether? as it could leak there ? Captain Dangerous